Code and data spatial complexity: two important software understandability measures

In order to maintain the software, the programmers need to understand the source code. The understandability of the source code depends upon the psychological complexity of the software, and it requires cognitive abilities to understand the source code. The individual needs to correlate the orientation and location of various entities with their processing, which requires spatial abilities. This paper presents two measures of spatial complexity, which are based on two important aspects of the program-code as well as data. The measures have been applied to 15 different software projects and results have been used to draw many conclusions. The validation of the results has been done with help of perfective maintenance data. Lower values of code as well as data spatial complexity denote better understandability of the source code. (C) 2003 Elsevier Science B.V. All rights reserved.